Recombinant human glycosylasparaginase catalyzes hydrolysis of l‐asparagine

FEBS Letters

Stoineva, Ivanka B.²  Mononen, Ilkka¹  Noronkoski, Tiina¹  Petkov, Dimiter D.² 

[1] Department of Clinical Chemistry, Kuopio University Hospital, P.O. Box 1777, FIN-70211 Kuopio, Finland;Laboratory of BioCatalysis, Institute of Organic Chemistry, Bulgarian Academy of Sciences, BG-1113 Sofia, Bulgaria

关键词: Glycosylasparaginase;    Lysosomal enzyme;    Asparaginase;    l-asparagine metabolism;    Asn;    l-asparagine;    Asp;    l-aspartic acid;    AspAMC;    l-aspartic acid β-(7-amido-4-methylcoumarin);    GA;    glycosylasparaginase;    AGU;    aspartylglycosaminuria;    HPLC;    high-performance liquid chromatography;    SDS-PAGE;    sodiumdodecylsulphate polyacrylamide gel electrophoresis;    GlcNAc-Asn;    N 4-(β-N-acetyl-d-glucosaminyl)-l-asparagine;    2-acetamido-1-l-β-aspartamido-1;    2-dideoxy-β-d-glucose;    aspartylglucosamine;    CmCys;    carboxymethylcysteine;    PITC;    phenylisothiocyanate;   

DOI  :  10.1016/S0014-5793(97)00761-8

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Glycosylasparaginase is a lysosomal amidase involved in the degradation of glycoproteins. Recombinant human glycosylasparaginase is capable of catalyzing the hydrolysis of the amino acid l-asparagine to l-aspartic acid and ammonia. For the hydrolysis of l-asparagine the K _m is 3–4-fold higher and V _max 1/5 of that for glycoasparagines suggesting that the full catalytic potential of glycosylasparaginase is not used in the hydrolysis of the free amino acid. l-Asparagine competitively inhibits the hydrolysis of aspartylglucosamine indicating that both the amino acid and glycoasparagine are interacting with the same active site of the enzyme. The hydrolytic mechanism of l-asparagine and glycoasparagines will be discussed.

【 授权许可】

Unknown